(Reuters) - British drugmaker Indivior Plc lost nearly three-quarters of its share value on Wednesday and former parent Reckitt Benckiser also fell following U.S. criminal charges accusing Indivior of illegally increasing prescriptions for its opioid addiction treatment Suboxone.

In an indictment in federal court in Abingdon, Virginia, a grand jury said Indivior made billions of dollars by deceiving doctors and healthcare benefit programs into believing its Suboxone Film version was safer and less susceptible to abuse than similar drugs.

The indictment charged Indivior and its subsidiary Indivior Inc with conspiracy, health care fraud, mail fraud and wire fraud. If the company is convicted, the U.S. government would seek forfeiture of at least $3 billion from Indivior, the indictment said.

The company has set aside a provision of $438 million related to the issue.

Indivior developed the film version of the treatment as a period of marketing exclusivity granted by the U.S. Federal Drug Administration (FDA) for the tablet form of the drug - itself a kind of opioid - was coming to an end, opening it up to generic competition.

Indivior had prospered as U.S. officials stepped up efforts to combat an opioid epidemic that President Donald Trump has declared a public health emergency. U.S. sales account for 80 percent of last year’s $1 billion in revenue.

Shares, however, had already been hurt by expectations of a slump in Suboxone sales with the arrival of new generic competition this year. Indivior has struggled to convince analysts and financial investors that it has an adequate replacement.

Suboxone film is used by people recovering from opioid dependency. Indivior used a telephone program to connect patients to doctors that the company “knew were prescribing Suboxone and/or other opioids in a careless and clinically unwarranted manner,” the indictment said.

Slough, England-based Indivior said that “an adverse verdict may have a material adverse effect on the company and its financial position and outlook.” A court hearing is scheduled for May 6 and the company plans to plead not guilty to the charges, a spokesman said.

‘FALSE STATEMENTS’

Indivior shares crashed to an all-time low and wiped out over 550 million pounds ($720 million) in market value. They closed down 71.6 percent at 30.05 pence. Close to 100 million shares changed hands, roughly 40 times the 30-day daily average volume.

Reckitt Benckiser was not charged, but the indictment said the illegal behavior began before it spun off Indivior in 2014. It refers to Indivior’s owner until then as “Company A”.

Reckitt shares slumped 6.5 percent to the bottom of London’s blue chip FTSE 100 index, erasing many of the gains made in 2019 after three tough years.

The indictment said that executives of “Company A” made or approved “false statements” that the film version of Suboxone was safer to have around children than the discontinued tablet, “even though they knew the primary reason for the discontinuance was to delay FDA approval of generic Suboxone”.

“This indictment is not against RB Group Plc or any other group company and we currently have no additional or new information in respect of this matter, apart from what has been publicly issued by the Department of Justice and Indivior Plc,” Reckitt, owner of Durex condoms and Lysol cleaners, said in a statement on Wednesday.

It referred investors back to a previous statement that it was recognizing a provision of $400 million relating to the issue but that its final cost could be substantially higher.

The provision is in case Reckitt should itself be indicted, as the company has indemnification against liabilities arising from charges against Indivior, a spokeswoman said.

Reckitt was just starting to regain investor confidence after a series of one-off problems including a safety scandal in South Korea, a failed product launch, a cyber attack and a manufacturing glitch.

Its chief executive Rakesh Kapoor, who oversaw several acquisitions and divestitures with the aim of turning Reckitt into a global consumer healthcare company, will retire this year, even though a major undertaking - splitting Reckitt into two business units - is unfinished.

Kapoor took the reins at Reckitt in September 2011. Many of the allegations in the indictment relate to activities before this period, when Reckitt’s CEO was Bart Becht, who took Benckiser public in 1997 and merged it with Reckitt & Coleman two years later.

Reuters could not immediately reach Becht for comment on Wednesday.

The potential penalty against Indivior is triple the annual revenue it made last year, or slightly more than the total revenue the company made from Suboxone film from 2010 to 2014. Indivior had net cash of $681 million at the end of the year.

Jefferies analysts said in a note: “The headline potential penalties are severe but a settlement is also still possible.”

Last year, Indivior said it was in “advanced discussions” with the U.S. Department of Justice about a possible resolution but none has emerged.

Indivior has spent the last two years fighting multiple legal battles and patent disputes in the United States with companies including Dr.Reddy’s, Teva and Mylan to block them from launching generic versions of Suboxone film.

(Graphic: Reckitt erases most of 2019 gains after three tough years - tmsnrt.rs/2D8Hyj1)

RECKITT FEARS

Reckitt’s spin-off of Indivior in 2014 and the 2017 sale of Reckitt’s food unit, let Reckitt focus on expanding its consumer health business, which targets ageing populations and those interested in health and wellness in the West and rising incomes in developing markets.

In addition to concern about Reckitt’s liability, investors on Wednesday worried about a possible spillover effect on Reckitt’s infant formula business.

The company had previously flagged implications including “potential criminal indictment of the group or employees, with reputational impact, distraction and potential debarment which could theoretically extend” to its infant formula business.

The business, which sells Enfamil formula, derives a portion of its sales from government contracts in the United States supplying a program to support low-income parents.

However, Reckitt said on Wednesday any risk to the infant formula business was theoretical and seen as “highly unlikely and only a remote possibility”.

Reporting by Justin George Varghese and Martinne Geller; Additional reporting by Nate Raymond in New York and Thyagaraju Adinarayan in London; Editing by Keith Weir, David Evans and Grant McCool